-use rustc::lint::in_external_macro;
use rustc_ast::ast::{Expr, ExprKind};
use rustc_lint::{EarlyContext, EarlyLintPass, LintContext};
+use rustc_middle::lint::in_external_macro;
use rustc_session::{declare_lint_pass, declare_tool_lint};
use crate::utils::span_lint_and_help;
declare_clippy_lint! {
/// **What it does:** Checks for usage of `as` conversions.
///
+ /// Note that this lint is specialized in linting *every single* use of `as`
+ /// regardless of whether good alternatives exist or not.
+ /// If you want more precise lints for `as`, please consider using these separate lints:
+ /// `unnecessary_cast`, `cast_lossless/possible_truncation/possible_wrap/precision_loss/sign_loss`,
+ /// `fn_to_numeric_cast(_with_truncation)`, `char_lit_as_u8`, `ref_to_mut` and `ptr_as_ptr`.
+ /// There is a good explanation the reason why this lint should work in this way and how it is useful
+ /// [in this issue](https://github.com/rust-lang/rust-clippy/issues/5122).
+ ///
/// **Why is this bad?** `as` conversions will perform many kinds of
/// conversions, including silently lossy conversions and dangerous coercions.
/// There are cases when it makes sense to use `as`, so the lint is
AS_CONVERSIONS,
expr.span,
"using a potentially dangerous silent `as` conversion",
+ None,
"consider using a safe wrapper for this conversion",
);
}